Organo-phosphorus compounds



ORGANO-PHOSPHORUS COMPOUNDS Van R. Gaertner, Dayton, Ohio, assignor toMonsanto Chemical Company, St. Louis, Mo., a corporation of Missouri eNo Drawing. Filed Aug. 11, 19 58, Ser. No. 754,151'

18 'Claims. (Cl. 260-461) This invention relates to the reaction ofalkanesultones with esters of organo-phosphorus compounds in which thephosphorus atom is trivalent and to the products thereof. The presentapplication is a continuation-inpart of my copending, applicationsSerial No. 542,499 filed October 24, 1955, now abandoned and Serial No.601,104 filed July 31,1956, now abandoned.

When tertiary phosphite esters are reacted with organic sulfonylhalides, it is reported (U.S. 2,690,450 that a phosphonothioate .isformed. On the other hand, the literature indicates that treatment of atertiary phosphite ester with an organic sulfonate ester gives aphosphonate which is free of sulfur (J. Amer. Chem. Sor. 1954, 76,4172).

In accordance with the present invention, sultones are reacted withorgano-phosphorus compounds in which at least one residual valence issatisfied by acidic derivative function. The organo-phosphorus compoundswhich are useful in the present process include phosphonous, phosphinousand phosphonic acid compounds. Particularly useful in the process of theinvention are the phosphonite, phosphinite and phosphite esters or thethio analogs thereof.

I have now discovered that new and valuable compounds containingphosphonic, phosphonous or phosphinous and sulfonic acid groups areobtained when an alkanesulton eis reacted with a phosphonite,phosphinite or phosphite ester. The primary reaction product is anester; but by pyrolysis or other suitable means, e.g. hydrolysis, theester can be converted to the dior monoesters or the free acid. The overall reaction can be represented by the following equation:

Wherein R is an organic radical free of non-benzenoid unsaturationcontaining from 1 to 12 carbon atoms, R is a saturated hydrocarbonradical of from 3 to 7 carbon atoms, R is selected from the classconsisting of hydrogen and hydrocarbon radicals free of non-benzenoidunsaturation and containing from 1 to 12 carbon atoms, R' is selectedfrom the class consisting of hydrogen and R, A is a chalcogen elementselected from the class consisting of oxygen and sulfur, and B is aradical selected from the class consisting of R and AR. By nonbenzenoidunsaturation is here meant olefinic and acetylenic unsaturation whichtypes of unsaturation are known in the chemical art to differ inreactivity from aromatic, i.e., benzenoid unsaturation.

The sultones employed in the preparation of the present compounds ,arereadily available compounds which may be prepared, e.g., bysulfochlorination of an organic halide, hydrolysis of the halogenatedorganic 2,957,905 Patented Oct. 25, 1960 7 ice sulfonyl chloride therebyformed, and ring-closure of the hydrolysis product, with evolution ofhydrogen halide, yielding the sultone. Whereas sultones are preferablynamed as derivatives of the corresponding hydroxy sulfonic acid, i.e.,

CHZOHZCHZSOQ In a preferred embodiment of the present reaction, sultonesof the formula are used, where R is a hydrocarbon radical'containingfrom 3 to 7 carbon atoms, and R" is selected fromthe class consisting ofhydrogen and hydrocarbon radicals free of aliphatic unsaturati'on andcontaining from 1 to 12 carbon atoms. These include, e.g.,propanesulton'e, butanesultone, isooctanesultone, tert-dodecauesultone,n-hexadecanesultone, kerosenesultone, etc. As examples of specificuseful sultones may be listed, e.g., alkanesultones such as the sultoneof 3-hydroxy-l-propanesulfonic acid, the sultone of4-hydroxy-2-methyl-2-butantesulfonic acid, the sultone ofS-hydroxy-l-pentantesulfonic acid, acid, the sultone ofS-hydrbxy-l-pentanesulfonic acid, the sultone of7,7-di-tert-dodecyl4-hydroxy-1-heptanesulfonic acid, etc., and arene-,aralkane-, and cycloalkanesultones such as the sultone of3-hydroxy-3-phenyl l-propanesulfonic acid, the sultone of4-hydroxy-2,4-diphenyl-l-butanesulfonic acid, etc.

Phosphorus compounds useful in the process of the invention includephosphonite, phosphinite and phosphite esters, or their thio analogs.Particularly preferred are the alkyl and chloroalkyl esters ofphosphonous, phosphinous and phosphorus acids. The organic radicalattached directly to phosphorus by a carbon-phosphorous bond andtheester radical in these esters can be a hydrocarbon radical or asubstituted hydrocarbon radical wherein thesubstituents do not interferein the course of the present reaction with sultones; but it is preferredthat at least one ester-forming radical is an alkyl or aralkyl groups inwhich the carbon atom attached to the oxygen or sulfur atom of the estergroup is aliphatic, e.g., the triaryl phosphites undergo the presentreaction, but require substantially elevated temperatures to produceformation of the desired tertiary esters of phosphonoalkanesulfonic acidcompounds. Examples of such noninterfering substituents are cyano,carbalkoxy and alkoxy radicals, and nuclearly substituted halogen atomson aryl radicals. The tertiary phosphite esters useful in the presentreaction can be prepared, eg by the reaction of K the correspondingalcohol or mercaptan with phos- Examples of presently useful phosphoniteesters wherein the organic radicals bonded directly to the phosphorousatom are hydrocarbon radicals, and which may be reacted with sultone inaccordance with the present invention are, for example,alkyl-phosphonite esters such as dimethyl ethylphosphonite, diethylethylphosphonite, dipropyl ethylphosphonite, diisopropylethylphosphonite, dibutyl ethylphosphonite, dihexyl ethylphosphonite,din-octyl ethylphosphonite, di-Z-ethylhexyl ethylphosphonite, methylethyl ethylphosphonite, phenyl methyl ethylphosphonite, diethylpropylphosphonite, diethyl isopropylphosphonite, diisopropylisopropylphosphonite, diethyl isobutylphosphonite, diisobutylisobutylphosphonite, diethyl isoamylphosphonite, diisopropylisoamylphosphonite, dioctyl heptylphosphonite, dioctyln-octylphosphonite, diethyl dodecylphosphonite, di-n-octyldecylphosphonite, butyl p-isoamylphenyl ethylphosphonite, etc.; as wellas esters of cycloalkyl phosphonous acids, such as diethylcyclohexylphosphonite; esters of aralkylphosphonous acids, such asdiethyl benzylphosphonite, diethyl 3-phenylhexylphosphonite, dibutylbenzylphosphonite, etc.; esters of arylphosphonous acids, such asdiethyl phenylphosphonite, diisobutyl phenylphosphonite, diethyl4-biphenylylphosphonite, dibutyl phenylphosphonite, diisoamylphenylphosphonite, diisopropyl p-tolylphosphonite, dibutylp-tolylphosphonite, etc.; and esters of thiophosphonous acids, such asdiethyl ethylphosphonothioate, dimethyl ethylphosphonodithioate, etc.

Examples of phosphonite esters in which non-interfering substituents arepresent on the organic radical attached directly to the phosphorus atomby a carbonto-phosphorus bond are e.g., diethyl 4-cyanobutylphosphonite,diethyl 2-ethoxyethylphosphonite, diethyl pchlorophenylphosphonite,diethyl p-bromophenylphosphonite, diethyl p-methoxyphenylphosphonite,dibutyl prnethoxyphenylphosphonite, diethyl p-ethoxyphenylphosphonite,diethyl 3 chloro 4 methylphenylphosphonite, ethyl2-(diisopropoxyphosphino)-p-toluate, etc.

Phosphinite esters useful in the present reaction Wherein the organicradicals bonded directly to the phosphorus atoms are hydrocarbonradicals are, for example, ethyl diethylphosphinite, ethyldipropylphosphinite, ethyl dibutylphosphinite, methylmethylethylphosphinite, ethyl diphenylphosphinite, isopropyldiphenylphosphinite, dodecyl diphenylphosphinite, ethylphenyltolylphosphinite, ethyl ethyl(o,p-di-n-propylphenyl)phosphinite,octyl dicyclohexylphosphinite, amyl dibenzylphosphinite, ethyldi-o-tolylphosphinite, ethyl phenyl-p-tolylphosphinite, ethyldi-p-tolylphosphinite, isoamyl di(p-isoamylphenyl)- phosphinite, etc.Also useful in the present process are phosphinite esters wherein theorganic radical bonded directly to the phosphorus atom by a carbon atomis a substituted hydrocarbon radical wherein the substituent is onewhich does not interfere in the present reaction, such as ethyldi(o-chlorophenyl)phosphinite, ethyl di- (p-chlorophenyl)-phosphinite,ethyl di(p-ethoxyphenyl) phosphinite, etc., and esters ofthiophosphinous acids, such as ethyl dimethylphosphinothioate, ethyldiethylphosphinothioate, etc.

Particularly useful in the present reaction are the tertiary alkylesters of phosphorous acid. One class of such alkyl phosphites includesthe trialkyl phosphites. As examples of trialkyl phosphites in which allthree ester groups are identical may be listed trimethyl phosphite,triethyl phosphite, tripropyl phosphite, triisopropyl phosphite,tri-n-butyl phosphite, tri-tert-butyl phosphite, triisoamyl phosphite,trihexyl phosphite, tris(Z-ethylhexyl) phosphite, tri-n-octyl phosphite,tri-tert-decyl phosphite, triisododecyl phosphite, tris(Z-butyloctyl)phosphite, trihexadecyl phosphite, tri-sec-butyl phosphite, etc.Examples of trialkyl phosphites in which different alkyl ester groupsare present are diethyl methyl phosphite, dipropyl butyl phosphite,di-n-butyl propyl phosphite, ethyl 2-butyloctyl hexyl phosphite,diisopropyl hexadecyl phosphite, etc.

Also useful in the present process are tertiary phosphite esters of theabove formula which contain alkenyl groups, i.e., 1-methyl-3-pentenyldiethyl phosphite, 3- vinylisodecyl diethyl phosphite, bis(4-vinylhexyl)isopropyl phosphite, tris(4-butyl-5-dodecenyl) phosphite, etc.

Another class of tertiary phosphite esters which undergo the presentreaction with alkanesultones comprises the aryl phosphite esters. Theseinclude, e.g., triaryl esters such as triphenyl phosphite, tri-p-tolylphosphite, etc.; particularly preferred in the present process are thediaryl alkyl and dialkyl aryl phosphite esters such as diphenyl ethylphosphite, diethyl phenyl phosphite, di-o-tolyl butyl phosphite,bis(2-ethylhexyl) phenyl phosphite, di-isohexyl l-naphthyl phosphite,dinonyl phenyl phosphite, bis(2-butyldecyl) phenyl phosphite, diethylptolyl phosphite, etc.

Useful in the process of the present invention are also the classes ofaralkyl and cycloalkyl phosphite tertiary esters. As examples of aralkylphosphite esters may be listed, e.g., triphenethyl phosphite,tris(3-phenylbutyl) phosphite, 3-phenylpropyl diethyl phosphite, etc.Cycloalkyl esters of phosphorous acid useful in the present process are,e.g., tricyclohexyl phosphite, cyclohexyl diethyl phosphite, cyclopentylhexadecyl butyl phosphite, etc.

Also included in the scope of the present invention are thephosphonoalkanesulfonic acid compounds prepared from tertiary phosphiteesters such as those described above in which the ester radical includessubstituents which do not interfere with the course of the reaction withsultones. Such substituents include, for example, halogen atoms, alkoxyradicals, carbalkoxy radicals, and cyano radicals. The class ofhalogenated tertiary phosphite esters useful in the preparation of thepresent compounds includes, e.g., tris(2-chloroethyl) phosphite,tris(2,2,2-trichloroethyl) phosphite, 2-chloroethyl diethyl phosphite,2-chloroethyl di-n-butyl phosphite, p-chlorophenyl dibutyl phosphite,etc. Examples of the class of alkoxy-substituted tertiary phosphiteesters which undergo the present reaction are tris (methoxymethyl)phosphite, tris(2-ethoxyethyl) phosphite, tris- (4-ethoxybutyl)phosphite, 2-(2-methoxyethoxy)ethyl dimethyl phosphite,2-butoxyisopropyl diisopropyl phosphite, tris(Z-butoxyethyl) phosphite,trisEZ-(methoxymethoxy)ethyl] phosphite, o-methoxyphenyl diethylphosphite, p-methoxyphenethyl bis(2-ethylhexyl) phosphite, etc.Carbalkoxyalkyl tertiary phosphite esters useful in preparing thepresent compounds include, e.g., tris(Z-carbethoxyethyl) phosphite,tris(carboisobutoxymethyl) phosphite, l-carbethoxyethyl diethylphosphite, etc. Cyanoalkyl phosphite esters useful in the process ofthis invention include, e.g., tris(3-cyano-l-propyl) phosphite,tris(2-cyanoethyl) phosphite, etc.

Another class of phosphite tertiary esters contemplated for use in thepresent process includes the cyclic phosphite esters. For example,glycol alkyl tertiary phosphite esters such as ethylene methylphosphite, ethyl propylene phosphite, 2-chloroethyl propylene phosphite,butyl Z-methylpropylene phosphite, ethyl methoxymethylethylenephosphite, ethyl l-methylpropylene phosphite, chloromethylethylene butylphosphite, butylene methyl phosphite, etc., may be reacted with sultonesas described above. Also useful in the present preparation are cyclicesters of phosphorous acid with a monohydric alkyl alcohol and adihydric aryl alcohol, i.e., methyl o-phenylene phosphite, butylo-phenylene phosphite, isobutyl ophenylene phosphite, etc.

A further class of tertiary phosphite esters useful in the reaction ofthe invention are the thiophosphites in which one, two or three of theoxygen atoms of the ester groups have been replaced by a sulfur atom,i.e., phosphorothious, phosphorodithious and phosphorotrithious acids.Particularly preferred in the present process are the monoand'dithiophosphite tertiary esters,

i.e.-, triethyl 'phosphorothioite, triethyl phosphorodithioite,tripropyl phosphorothioite, diethyl propyl phosphorodithioite, etc. V pIn accordance with thepresent invention; phosphonite and phosphiniteesters are reacted with sultones to give phosphinylalkanesulfonates inwhich at least two organic radicals are attached directly to thephosphorus atom of the phosphinylalkanesulfonate compound by acarbonto-phosphorus. bond. Exemplary products which may be prepared bythe process of the invention utilizing alkyl hydrocarbon-phosphoniteesters are:

methyl 3-(ethylmethoxyphosphinyl)-1 propanesulfonate, ethyl3(ethylethoxyphosphinyl) -1-propanesulfonate, isopropyl4-(ethylethoxyphosphinyD-l-butanesulfonate, hexyl3-(hexylhexoxyphosphinyl)-1-propanesulfonate, octyl3-(ethylethoxyphosphiny1) -l-propanesulfonate, 2-ethylhexyl3-(etliyl(2-ethylhexoxy)phosphinyl)-1-propanesulfonate, dodecyl3-ethylethoxyphosphinyl)-1-propanesu1fonate, ethyl 3-(propylethoxyphosphinyl) -l-propanesulfonate, ethyl4-(isopropylethoxyphosphinyl) -1-butanesulfonate,- ethyl4-(isoamylethoxyphosphinyl)-2,3-dimethyl-1 hep-j tanesulfonate, ethyl5-(n-octylethoxyphosphinyl)-5,5-diamyl- 2 dodecanesulfonate', butyl 4'-(butoxypropylphosphinyl)-2-pentanesulfonate, isobutyl3-(isobutylisobutoxyphosphinyl) l-propanesulfo nate, Z-ethylhexyl3-('ethyKZ ethyIheXoXy)-phosphinyl)-l-pro panesulfonate; methyl4-(ethylnonoxyphosphinyl)-1-butanesulfonate, ethyl 3-(isoamyldodecoxyphosphinyl -1-propanesulfonate, ethyl3-(phenylethoxyphosphinyl)-1-propanesulfonate, t-butyl4-(phenyl-t-butoxyphosphinyl)-2-ethyl-1 butanesulfonate, ethyl 4-(p-tolylethoxyphosphinyl)-2-pentanesulfonate. ethyl3-[(diisopropylphenyl)ethoxyphosphinyl) 1-1 propanesulfonate, propyl4-(cyclohexylpropoxyphosphinyl)-2,3-dimethyl-1 heptanesulfonate, etc.

Examples of products of the reaction of sultones with alkyl esters ofphosphinites in which the organic radical attached to the phosphorusatom by a carbon-to-phosphorus bondcontains a non-interferingsubstituent are:

ethyl 3-(p-chlorophenylethoxyphosphinyl)-1-propanesulfonate,

ethyl 4-(p-chlorophenylethoxyphosphinyl)-1-butanesulfonate,

ethyl 3-(p-bromophenylethoxyphosphinyl)-l-propanesulfonate,

ethyl 3-[ (p-methoxyphenyl)-propoxyphosphinyl] -1-propanesulfonate,

ethyl 3-[ethoxy(p-ethoxyphenyl)phosphinyl]-1-propane sulfonate,

ethyl 4-[ethoxy(p-ethoxyphenyl)phosphinyl]-2-pentanesulfonate, etc.;

and thio analogs such as ethyl 3- [ethy1(ethylthio) phosphinyl]-1-pr0panesulfonate,

ethyl 3 [ethyl ethoxy) thionophosphinyl] l-prop anesulfonate,

ethyl 3 [ethyl (ethylthio) thionophosphinyl] -1-propanesulfonate, etc.

By the reaction of presently useful phosphinites With sultones areobtained the novel compounds of the above formula wherein the organicradicals are bonded to the phosphorus atom directly by carbon atoms.Examples of such products formed in accordance with this invention are:

ethyl B-(ethylmethylphosphinyl) -1-propanesulfonate, ethyl3-(diethylphosphinyl )'-l-propanesulfonate, ethyl3-(di-n-propylphosphinyl)-1-propanesulfonate, ethyl4-(dibutylphosphinyl) -1-butanesulfonate,

ethyl 3-(dicyclohexylphosphinyl)-1-propanesulfonate,

ethyl 4-(methylphenylphosphinyl)-2-pentanesulfonate,

ethyl 3-(ethylphenylphosphinyl)-1-propanesulfonate,

ethyl S-(diphenylphosphinyl)-1-propanesulfonate,

ethyl 4.- (diphenylphosphinyl) -2-ethyl-l-butanesulfonate;

ethyl S-(di-o-tolylphosphinyl)-1-propanesulfonate,

ethyl. 4- (.di-o-tolylphosphinyl)-1-t-dodecanesulfonate,

isopropyl 3"(diisopropylphosphinyl)-l-propanesulfonate,

isopropyl 3-(diamylphosphinyl) -1-butanesu1fonate,

isopropyl 5-[di-(2-ethylhexyl)phosphinyl]-2-dodecanesulfonate,

isopropyl 3-(isopropylphenylphosphinyl).-1-propanesulfonate,

n-propyl S-(diethylphosphinyl)-1-propanesulfonate,

isobutyl S-(dibenzylphosphinyl)-2-phenyl-l-propanesulfonate,

dodecyl 4-(diethylphosphinyl) -3-ethyl-1-hexadecanesulfonate,

dodecyl 3"- (di-4-biphenylylphosphinyl)- 1 propanesulfonate,

dodecyl 3-(did'odecylphosphinyl) -2-dodecanesulfonate,

ethyl 3-(di-o-chlorophenylphosphinyl)- 1 propanesulfonate,

ethyl 3-(di-p-chlorophenylphosphinyl)- 1 propanesulfonate,

ethyl 4-(di-o-chlorophenylphosphinyl)-l-butanesulfonate,

ethyl 3 [di- (p-methoxyphenyl)phosphinyl]-1 propanesulfonate, etc.;

and thio analogs such as ethyl3-(diethylthionophosphinyl)-l-propanesulfonate, etc.

The primary reaction products of alkanesultones and tertiaryphosphiteesters are, as shown above, tertiary esters of phosphonoalkanesulfonicacids, of the formula where R, R, R" and A are as defined above. Thereaction products of trialkyl. phosphites and alkanesultones of. the.above formulav are named as alkyl (dialkoxyphosphono)a'llianesulfonates.As examples of the compounds which may be made by the present processWithsuch reactants may be listed; e.g.:

ethyl 3"- diethoxyphosphono) -l-propanesulfonate,

isopropyl 3-(diisopropoxyphosphono) -l-propanesulfonate,

n-butyl 3-(dir-n-butoxyphosphono) -l-propanesulfonate,

tert-amyl 4-(di-tert-amoxyphosphono) -l-butanesulf0nate,

2-ethylhexyl 3-[bis(2- ethylhexoxy)phosphono] l propanesulfonate,

2-butyloctyl. 3- [bis (2-butyloctoxy) phosphono] -1-propanesulfonate,

n-hexyl 5-(dihexoxyphosphono)-1-pentanesulfonate ethyl4-(diethoxyphosphono)-2-methyl-l-butanesulfonate,

propyl 4-(dipropoxyphosphono)-2-butanesulfonate,

isobutyl 3-(diisobutoxyphosphono)-1-phenyl-l-propanesulfonate,

tert-dodecyl 4-(di-tert-dodecoxyphosphono)-l-tert-dodecanesulfonate,

.ethyl 3-(diisopropoxyphosphono) -l-propanesulfonate,

n-butyl 3-(O-n-butoxy-O-hexoxyphosphono)-l-propanesulfonate,

isooctyl 4-(diisoctoxyphosphono) -l-octanesulfonate,

methyl 5-(O-ethoxy-O'-propoxyphosphono).-l-pentanesulfonate, etc.

Reaction of alkanesultones with trialkyl phosphites having substituentson the alkyl groups gives, e.g.:

2-chloroethyl 3-[bis(2-chloroethoxy)phosphonol-l-propanesulfonate,

Z-bromoethyl 4-[bis(2-brornoethoxy)phosphono]-1 butanesulfonate,

2-chlorobutyl4[bis(2-chlorobutoxy)phosphono]-2-phenyl-l-butanesulfonate,

Cyclic phosphite esters reacted with alkanesultones in accordance withthe present invention give, e.g.:

methyl 3-( 1,3-propylenedioxyphosphono) -1-propanesulfonate, chloroethyl3-(Z-methyl-l,3-propylenedioxyphosphono)- l-butanesulfonate, chloroethyl4-( 1,2-diethyl-1 ,2-ethylenedioxyphosphono 2-phenyl-l-butanesulfonate,etc.

Aryl alkyl phosphite esters reacted with alkanesultones give, e.g.:

ethyl 3-(O-ethoxy-O-phenoxyphosphono)-1-propanesulfonate,

2-ethylhexyl 4-[O-(Z-ethylhexoxy)-O'-o-toloxyphospho no]-l-butanesulfonate,

2-chloroethyl 3-(diphenoxyphosphono)-4,4-diphenyl-1- pentanesulfonate,

n-butyl 4- [O- (2-butyloctoxy) -O'-phenoxyphosphono] -1-butanesulfonate, etc.

Products of reaction of phosphorothioite esters with alkane sultonesare, e. g.:

ethyl 3-(diethoxythionophosphono)-1-propanesulfonate,

Z-chlorobutyl 3-(diethoxythionophosphono)-1-propanesulfonate,

2-ethoxyethyl 4-[bis(2-ethoxyethoxy)thionophosphono]- l-butanesulfonate,

2-ethylhexyl3-[O,S-bis(2-ethylhexoxy)-thiolothionophosphonol-l-octanesulfonate, etc.

As mentioned above, pyrolysis of the tertiary esters ofphosphonoalkanesulfonic acids produced in accordance with the presentinvention yields the secondary and primary esters of these acids, and ifdesired, the free acids themselves may also be produced by pyrolysis,hydrolysis, etc. Pyrolysis of the tertiary esters of the presentphosphonoalkanesulfonic acids to give the secondary esters of theseacids may be represented schematically by the following equation, forexample:

where R, R and R" are as herein defined above. Thethiophosphonoalkanesulfonate esters are equivalent to thephosphonoalkanesulfonate esters for the purpose of this invention. Inthe above equation also, the ester group pyrolyzed off is shown as alkylhydrocarbon for the sake of convenience, to illustrate the formation ofan olefinic compound in this reaction; as discussed hereinabove,ester-forming groups bearing substituents such as alkoxy groups, etc.,are equally included in the concept of this invention. It will be notedthat the esterforming group on the sulfonic acid group is shown as beingcleaved in the above equation. The phosphonic acid ester groups mayequally be converted to free acid groups by the processes of thisinvention, and the nontertiary esters of phosphonoalkanesulfonic acidcompounds covered by the concept of this invention in clude, e.g.,

alkyl (alkoxyphosphono)alkanesulfonates, alkylphosphonoalkanesulfonates, (dialkoxyphosphono)alkanesulfonic acids,(alkoxyphosphono) alkanesulfonic acids, and phosphonoalkanesulfonicacids.

In like manner from the corresponding phosphinylalkanesulfonatecompounds are formed, e.g.,

alkyl (alkylphosphinyl)alkanesulfonates, (alkylphosphinyl)alkanesulfonicacids, (alkylalkoxyphosphinyl)alkanesulfonic acids, and(dialkylphosphinyl)alkanesulfonic acids.

As examples of secondary esters of phosphonoalkanesulfonic acidcompounds provided by the present invention may be mentioned:

methyl S-(methoxyphosphono) l-propanesulfonate, 2-chloroethylB-(ethoxyphosphono)-1-butanesulfonate, isopropyl3-(isopropoxyphosphono)-1-propanesulfonate,S-(di-n-butoxyphosphono)-l-propanesulfonic acid, 3-[bis(2ethylhexoxy)phosphono] 1 propanesulfonic acid, ethyl4-(ethoxyphosphono)-2-methyl l-pentanesulfonate, Z-butoxyethyl 3-(2-butoxyethoxy) phosphono] -2-phenyll-propanesulfonate, isopropyl 4-(isopropoxyphosphono l-decanesulfonate, n-butyl4-(phenoxyphosphono)-l-pentanesulfonate, isopropyl3-(isopropoxythionophosphono)-1-propanesulfonate, etc.

Examples of primary esters of phosphonoalkanesulfonic acid compoundsprovided by the present invention are:

methyl 3-phosphono-l-propanesulfonate,

Z-butyloctyl 4-phosphono-l-pentanesulfonate,

2-chloroethyl 4-phosphono 2 propyl 1 tert-decanesulfonate,

2-(2-ethoxyethoxy)ethyl 3-phosphono-4,4-diphenyll-pentanesulfonate,

2-ethylhexyl 3-(thiophosphono)-1-propanesulfonate,

S-(nonoxyphosphono)-2,3-dimethyl 1 pentanesulfonic acid,

4-[2 (carbobutoxy) ethoxyphosphono] 2 phenyl-lbutanesulfonic acid, etc.

The free acids in which all three ester groups have been replaced byhydrogen atoms which may be prepared by the process of this inventioninclude, e.g.:

3-phosphono-l-propanesulfonic acid, 41phosphono-l-butanesulfonic acid,4-phosphono-l-pentanesulfonic acid, S-phosphono-l-pentanesulfonic acid,5-phosphono-2-pentanesulfonic acid,2,2-diInethyl-3-phosphono-l-propanesulfonic acid,3-phenyl-4-phosphono-l-butanesulfonic acid,5,6-dimethyl-4-phosphonol-heptanesulfonic acid,3-methyl-4-phenyl-4-phosphono-l-butanesulfonic acid, etc.

Some corresponding examples derived from phosphinylalkanesulfonatecompounds are:

ethyl 3- (ethylphosphinyl l-propanesulfonate,3-(ethylphosphinyl)-l-propanesulfonic acid,3-(ethylethoxyphosphinyl)-1-propanesulfonic acid,S-(diethylphosphinyl)-l-propanesulfonic acid, etc.

In preparing the products of the invention, I prefer to operatesubstantially as follows:

For example, the tertiary phosphite ester (phosphonite or phosphinite)is contacted with the sultone at an elevated temperature until reactionis complete. Suitable temperatures may range from, e.g., 50 C. up tobelow the decomposition temperature of the reactants, and will vary withthe nature of the reactants. While I have found that the reaction ofthe, alkanesultone with the tertiary phosphite. ester proceeds readilyat atmospheric pressure, superor sub'atmospheric pressures may beemployedif desired, e.g., to raise'or lower the reaction temperature.Catalysts, e.g'.', bases such as triphenylamine, may be used if desired,for example, to facilitate the reaction in the case of aryl esters.Solvents, such as benzene, hexane, dioxane, etc, are usually notrequired but may be included in the reaction mixture, e.g., tofacilitate stirring. Generally, approximately equimolecular amounts ofthe sultone and the tertiary phosphite ester will be reacted together,but -an excess of one of the components may be used if desired, sinceunreacted sultone or phosphite may readily be removed, e-.g., bydistillation, when the reaction is complete. Either the sultone and thephosphite estermay be mixed andthen, if necessary, heat applied, or oneof the reactants may be. added graduallyto the other. I have found thatre action is generally complete within from a few minutes to severalhours; as further described below, if heating of the reaction mixture iscontinued after reaction is complete, it is possible, at highertemperatures, to cause pyrolysis of the tertiary ester of thephosphonoalkanesulfcnate and consequent formation of the lower estersand/ or free-tribasic acid. When formation of the tertiary ester of thephosphonoalkanesulfonic acid is complete, unreacted sultone and tertiaryphosphite ester may be removed, e.g., by distillation, extraction, etc.;the phosphonoalkanesulfonic acid tertiary ester may thenbe purified ifdesired, e.g., by washing, chromatographing to remove acidic impurities,distilling, etc.

In preparing the lower, i.e., secondary and primary esters of thepresent phosphonoalkanesulfonic acid compounds, I may either purify andisolate the tertiary ester prepared as described above, or I may proceeddirectly to the formation of the lower esters by continued heating ofthe reaction mixture of phosphite esterand sultone beyond the point offormation of the tertiary phosphonoalkanesulfonate ester. The lattertertiary ester may be pyrolyzed at elevated temperature, i.e., attemperatures, for example, which are to 50 C. above their temperaturesof formation, eliminating the ester group in the form of an olefin, andgiving phosphonoallcanesulfonic acid compounds in which at least one ofthe three acid functions is present in the form of a free OH group.Alternatively, I may prepare phosphonoalkanesulfonic acid compoundscontaining free acid groups from the tertiary ester of the correspondingphosphonoallcanesulfonic acid, prepared as described above, by applyingto it any of the conventional means of hydrolyzing an ester to a freeacid, i.e., treatment with a mineral acid such as hydrochloric acid,etc.

The invention is further illustrated, but not limited, by the followingexamples:

EXAMPLE 1 Ethyl 3-(dz'eth0xyphosph0n0)-1-pr0panesulf0nate Calculated for09 21001 8 7 Found Percent O.. Percent H Percent S Percent P 10 EXAMPLE2 T he. monoand diisopropyl esters' of-i-phosphono-L proparzesuifonicacid A mixture of 41.6 grams (0.22 mole) of triisopropyl phosphite and24.4 grams (0.20 mole) of 'y-propanesultone was placed in a flaskequipped with a condenser and a cooled trap and heated. At' C. internaltemperature, the reaction became exothermic. The mixture was stirred;the temperature slowly rose to 144 C. and then fell after about 10minutes. After heating at C. for half an hour; some three grams-ofpropylene had been collected in the condenser trap; the triester hadbeen pyrolyzed into the monoand di-esters. To recover the latter, thereaction mixture was distilled at 5 mm. of mercury up to a pottemperature of C., giving 13 grams of faintly amber distillate. Theresidue was dissolved in 200 ml. of ether, treated with charcoal andfiltered; The filtrate was diluted with ether until a layer separated;the ether layer was decanted; and the residual oil was washed with etherand dried, giving 2.55 grams of the diisopropyl ester of 3=phosphono1-propanesulfonic acid, which dissolves in water to give a stronglyacidic solution, and analyzes as follows:

' Found Calculated for G H2 OePS Percent C 34. 94 37. 5 Percent HQ 7. 227. 52

, The ether layer, after separation of the diester as described above,was evaporated under a slight vacuum at 120 C., giving 29.0 grams or"the viscous, acidic, water-soluble monoisopropyl ester of3-phosphono-lpropanesulfonic acid, which was found by analysis tocontain 25.10 percent carbon.

EXAMPLE 3 n-Butyl 3-(di-n-buzoxyphosphono) -1-pr0panesulf0nate A mixtureof 40.0 grams of tri-n-butyl phosphite and 18.3' grams of'y-propanesultone was stirred at 150465 C. for an hour. After removal ofunreacted starting materials, there remained 32.8 grams of n-butyl3(di-nbutoxyphosphono)-1-propanesulfonate, which is a pale yellow,mobile oil, (n 1.4515), insoluble in water, and soluble in ether andbenzene. It analyzed as follows:

Found Calculated for OrsHaaOaPS Percent O 47.10 48. 3 Percent H- 8. 918. 92

EXAMPLE 4 Z-ethylhexyl 3- bis(2-ethylhex0xy phosphono] propanesulfonateFound Calculated for CnHmOdPS Percent O 69. 52 59. 9 Percent H 10. 7010. 63

"11 EXAMPLE 2-chl0r0ethyl 3-[bis(2-chloroethoxy)phosphonol-I-propanesulfonate Found Calculated for Percent: O 27. 53 27. 6 Percent 114. 66 4. 63 Percent 01 24. 46 27. 2

EXAMPLE 6 Preparation of ethyl 3-(ethoxyphenylphosphinyl) -1-propanesulfonate To a flask containing 21.8 g. (0.11 mole) of diethylphenylphosphonite at 120 C., 12.2 g. (0.10 mole) of 'y-propanesultone inml. of benzene was gradually added, drop by drop. Then the temperatureof the mixture was raised to 125-135 C., whereupon exothermic reactionbegan. This temperature range was maintained for about 40 minutes, afterwhich the benzene was removed from the reaction mixture under a lowvacuum. A 25 g. portion of the residue was distilled to remove unreactedstarting material at up to 170 C., 8.5 g. being collected up to thistemperature. The viscous, almost colorless residue from the distillationrepresented crude ethyl 3 (ethoxyphenylphosphinyl) 1 propanesulfonate;it weighed 16.0 and, after purification by passage over alumina, wasfound to contain 8.07% phosphorus ('C H O PS requires 9.67% P). Ethyl3-(ethoxyphenylphosphinyl)-1-propanesulfonate is toxic on contact to thelarge milkweed bug, Oncopeltus fasciatus, at a. concentration of 1% inacetone solution; it is toxic on contact to mosquito larvae, in 0.001%aqueous solution, and it possesses a stomach poison toxicity to Aphisgossypii.

Similarly, by the procedure as described above, the reaction of ethyldiisobutylphosphinite with fi-butanesultone gives ethyl4-(diisobutylphosphinyl)-1-butanesulfonate; the reaction of diethylp-chlorophenylphosphonite with v-propanesultone gives ethyl3-[(p-chl0rophenyl) ethoxyphosphinyl]-1-propanesulfonate, etc.

EXAMPLE 7 For evaluation of microbiological toxicity, 1% solutions ofeach of the products of Examples 1, 3 and 5 were prepared by dissolving100 mg. samples of the compounds in 10 ml. of acetone. A mixture of 2ml. of the solution of the test compound with 18 ml. of sterile nutrientagar was poured into a sterile Petri dish and allowed to harden. Theplates prepared in this way were each inoculated with a drop of a stockculture of M icrococcus pyogenes var. aureus on one side, and a drop ofa culture of Salmonella typhosa on the other side of the plate, and thenincubated 5 days at 25 C. It was found that the growth of S. typhosa wasinhibited by each of the three compounds tested, while M. pyogenesfailed to grow on the plates containing either the product of Example 1or the product of Example 3.

The present esters can be employed to prevent or retard bacterial attack.on leather, cotton, wood, plants, starches, and other organic material.These products of the in- 12 vcntion need be employed only in minoramounts to obtain the benefits of their physiologic activity againstpathogenic agents such as bacteria, and may be admixed, if desired, withinert carriers to facilitate their application to potential pathogenhosts in minimum bactericidal and bacteriosta-tic amounts.

The present esters are also active miticides. Each of the products ofExamples 1-5, above, was toxic to Tetranychus telarius (the two-spottedspider mite), when leaves infested with this organism were dipped in0.1% aqueous emulsion of the compounds. (Emulsifier L, which is reputedto be a polyalkylene glycol derivative of an alkylbenzenesulfonate, wasused as the emulsifying agent in these tests.) The esters were found topossess both immediate toxicity, to adult stages, and residual activity(after seven days) towards resting stages and eggs of the mites. Alsosusceptible to poisoning by the present sulfonates are other aphidspecies, such as cotton aphids (Aphis gossypii). The present esterswherein each acid function is esterified by a chlorine-substituted alkylradical are also toxic to the growth stages of true insects (Hexapoda),such as the Mexican bean beetle (Epilachna verivestis) larvae, yellowfever mosquito (Aedes aegypti) larvae, etc. The esters of the inventionmay be applied to insect and mite habitats either directly, in the formof the oily to solid products obtained as described above, or dilutedwith insecticide adjuvants, e.g., forming sprayable toxicants such asthe emulsion described above.

The phosphorus compounds of the invention are additionally active asherbicides. Applied to plants as the active herbicidal ingredient of afoilage spray, the products of the invention are phytotoxic to broadleafplants, and also exhibit some toxicity to grasses. For example, analuminum pan containing 10-20 two-week old seedlings each of radish,buckwheat, red clover, and sugar beet was sprayed with 15 cc. of an 0.5%aqueous emulsion (prepared with Emulsifier L) of n-butyl3-(di-nbutoxyphosphinyl)-1-propanesulfonate; this rate equalling about 9lbs/acre. After two weeks, the pan was observed; all of the seedlings ofthese four plant species were dead. Each of the other products of theabove examples similarly produced had marked phytotoxic symptoms, suchas chlorosis, leaf curl, etc., when applied to plants as a foilagespray.

For use as toxicants, the products of the invention can be dispersed ona finely divided solid and employed as a dust. Also, such mixtures canbe dispersed in water with the aid of a wetting agent, and the resultingaqueous dispersions applied to pest habitations as sprays. In otherprocedures, the products can be employed in oils, i.e., water-immiscibleorganic solvents, as constituents of oilin-water emulsions, or in waterdispersions, with or without the addition of wetting, dispersing, oremulsifying agents. Suitable emulsifying agents are the polyalkyleneglycol alkylbenzenesulfonate derivative listed above, and similaragricultural emulsifying adjuvants, such as are listed, e.g., in US.Dept. of Agriculture Bulletin E607. The amount of the present estersemployed in pesticidal compositions containing inert carriers will varywith the ester utilized, the manner of application, the organism whichit is sought to inhibit or kill, etc., and will be adjusted accordingly,the examples given above indicating representative concentrations fortoxicity against various organisms.

The new esters and acids of the invention are stable compounds whichrange from oils to semi-solid materials, which are generally soluble inorganic solvents. They are biological toxicants and are useful asinsecticides. The novel compounds afforded by the present reaction mayalso be used as components of agricultural pesticide compositions, suchas fungicides, bactericides, miticides, nematocides, herbicides, etc.The long-chain alkyl esters, i.e., those containing ester groups of from6 to 12 carbon atoms, particularly the alkyl, esters, may be used, forexample, as surface-active agents and as plasticizers.

13 Short-chain esters of the present formula may be applied asbacteriostats, e.g., in soap. The present compounds can also be utilizedas chemical intermediates, e.g., for conversion to the correspondingsulfonate metal salts, which may be used as oil additives.

What is claimed is:

1. The method which comprises heating above 50 C. an organophosphorusacid compound selected from the class consisting of (RA) P, (RA) R P and(RA) (R P wherein R is an alkyl radical having from 1 to 12 carbonatoms, R is a hydrocarbon radical free of non-benzenoid unsaturationhaving from 1 to 12 carbon atoms and A is a chalcogen element selectedfrom the class consisting of oxygen and sulfur, with an alkane sultoneselected from the class consisting of 'y and 6 sultones of the formulawherein R is a straight-chain saturated aliphatic hydrocarbon radical of3 to 4 carbon atoms, and R" is selected from the class consisting ofhydrogen and lower alkyl radicals, and isolating from the resultingproduct a compound of the formula RI! )zPit-SOBR'" wherein R is selectedfrom the class consisting of hydrogen and R and B is selected from theclass consisting of R and AR.

2. The process which comprises reacting propanesultone with a lowerdialkyl ester of phenylphosphonous acid, and isolating from theresulting reaction product a lower alkyl ester of 3-[(lower alko-xy)(phenyl)phosphinyl]1- propane sulfonic acid.

3. The process which comprises reacting propanesultone with diethylphenylphosphonite and isolating from the resulting reaction productethyl 3-[(ethoxy)phenylphosphinyl] -1-propanesulfonate.

4. The method which comprises heating together at above 50 a trialkylphosphite ester of the formula (Alk-O) P, wherein Alk is an alkylradical of from 1 to 16 carbon atoms with propanesultone of the formulaOHzOHzCHsSOt and isolating from the resulting reaction product thecorresponding alkyl 3-(dialkoxyphosphono)-1-propanesulfonate.

5. The method which comprises heating together at above 1 C.approximately equimolar amounts of triethyl phosphite and'y-propanesultone and isolating from the resulting reaction productethyl 3-(diethoxyphosphono)-1-propanesulfonate.

6. The method which comprises heating together at above 50 C.approximately equimolar amounts of triisopropyl phosphite and'y-propanesultone and recovering from the resulting reaction product anisopropyl ester of 3-phosphono-l-propane-sulfonio acid.

7. The method which comprises heating together at above C. approximatelyequimolar amounts of trin-butyl phosphite and 'y-propanesultone andisolating from the resulting reaction product n-butyl3-(di-n-butoxyphosphono) -51 -pro-panesulfonate.

8. The method which comprises heating together at above C. approximatelyequimolar amounts of his- (Z-ethylhexyl) phosphite and 'y-propanesultoneand isolating from the resulting reaction product TZ-ethylhexyl 3- [bis(Z-ethylhexoxy) -phosphono] -l-propanesulfonate.

9. The method which comprises heating together at above 50 C.approximately equirnolar amounts of his- (2-chloroethyl) phosphite and'y-propanesultone and recovering from the reaction product 2-chloroethyl3-[bis (2-ch1oroethoxy)phosphono]-1-propanesulfonate.

10. A compound of the formula wherein R is selected from the classconsisting of hydrogen and alkyl radicals having from 1 to -l2 carbonatoms, A is a chalcogen element selected from the class consisting ofoxygen and sulfur, R is a straight-chain saturated aliphatic hydrocarbonradical of from 3 to 4 carbon atoms providing for the joining of thephosphorus and sulfur atoms by 3 and 4 carbon atom chains, R" isselected from the class consisting of hydrogen and lower alkyl radicals,and B is selected from the class consisting of hydrocarbon radicals freeof non-benzenoid unsaturation having from 1 to 12 carbon atoms and AR!!!11. An isopropyl ester of 3-phosphono-1-propanesulfonic acid.

12. Lower alkyl esters of 3-[(lower alkoxy) (phenyl)- phosphinyl]-1-propanesulfionic acids.

:13. Ethyl 3-[ (ethoxy) (phenyl)phosphinyll-1-propanesulfonate.

14. Anester of the formula wherein R is an alkyl radical having from 1to 16 carbon atoms.

15. Ethyl 3-(diethoxyphosphono)-1propanesulfonate.

16. n-Butyl 3-(di-n-butoxyphosphono)-l-propanesulfonate.

l7. Z-ethylhexyl 3-[bis(2-ethylhexoxy)phosphono]-1- propanesulfonate.

1 8. Z-chloroethyl 3- [bis 2-chlor'oethoxy) phosphono]l-propanesulfonate.

References Cited in the file of this patent FOREIGN PATENTS 938,186Great Britain Jan. 26, 11956 UNITED STATES PATENT OFFICE CERTIFICATE OFCORRECTION Patent No. 2,957,905 October 25, 1960 Van R. Gaertner It ishereby certified that error appears in the above numbered patentrequiring correction and that the said Letters Patent should read ascorrected below.

Column 1, line 41, for "alkanesulton eis" read alkanesultone is lines 48to 54, the right-hand portion of the formula should appear as shownbelow instead of as in the patent:

I (B) P-R' SO R 2" 3 column 2, line 89, for "acid, the sultone ofS-hydroxy-l-= pentanesulfonic acid," read the sultone of 5-hydroxy-4-methyl-l-hexanesulfonic acid, line 56, for "groups" read group column 5,line 38, for "3-[(diisopropylphenyl) e. 1l;51oxyph0sphinyl)]-" read3[(diisopropylphenyl)ethoxyphosphiny Signed and sealed this lst day ofJanuary 1963.,

(SEAL) Attest:

ERNEST W. SWIDER D V L LADD Attesting Officer Commissioner of Patents

1. THE METHOD WHICH COMPRISES HEATING ABOVE 50*C. AN ORGANOPHOSPHORUSACID COMPOUND SELECTED FROM THE CLASS CONSISTING OF (RA)3P, (RA)2R1P AND(RA) (R1)2P WHEREIN R IS AN ALKYL RADICAL HAVING FROM 1 TO 12 CARBONATOMS, R1 IS A HYDROCARBON RADICAL FREE OF NON-BENZENOID UNSATURATIONHAVING FROM 1 TO 12 CARBON ATOMS AND A IS A CHALCOGEN ELEMENT SELECTEDFROM THE CLASS CONSISTING OF OXYGEN AND SULFUR, WITH AN ALKANE SULTONESELECTED FROM THE CLASS CONSISTING OF Y AND $ SULTONES OF THE FORMULA10. A COMPOUND OF THE FORMULA